Re: [PATCH] wifi: ath10k: Fix resource leak in ath10k_pci_init()

[xiujianfeng]

Hi,

在 2022/11/10 0:34, Jeff Johnson 写道:
> On 11/8/2022 5:38 AM, Xiu Jianfeng wrote:
> > When ath10k_ahb_init() fails, it does not unregister ath10k_pci_driver,
> > which will cause a resource leak issue, call pci_unregister_driver() in
> > the error path to fix this issue.
> >
> > Fixes: 0b523ced9a3c ("ath10k: add basic skeleton to support ahb")
> > Signed-off-by: Xiu Jianfeng <xiujianfeng@xxxxxxxxxx>
> > ---
> >   drivers/net/wireless/ath/ath10k/pci.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/net/wireless/ath/ath10k/pci.c 
> > b/drivers/net/wireless/ath/ath10k/pci.c
> > index e56c6a6b1379..22f8f8b20762 100644
> > --- a/drivers/net/wireless/ath/ath10k/pci.c
> > +++ b/drivers/net/wireless/ath/ath10k/pci.c
> > @@ -3800,8 +3800,10 @@ static int __init ath10k_pci_init(void)
> >                  ret);
> >       ret = ath10k_ahb_init();
> > -    if (ret)
> > +    if (ret) {
> >           printk(KERN_ERR "ahb init failed: %d\n", ret);
> > +        pci_unregister_driver(&ath10k_pci_driver);
> > +    }
> >       return ret;
> >   }
>
> imo neither the existing code nor the modified code is correct.
>
> the driver is attempting to register to support two different buses.
>
> if either of these is successful then ath10k_pci_init() should return 0 
> so that hardware attached to the successful bus can be probed and 
> supported.
>
> only if both of these are unsuccessful should ath10k_pci_init() return 
> an errno.
>
> so I suggest
>      int ret1, ret2;
>
>      ret1 = pci_register_driver(&ath10k_pci_driver);
>      if (ret1)
>          printk(KERN_ERR "failed to register ath10k pci driver: %d\n",
>                 ret1);
>
>      ret2 = ath10k_ahb_init();
>      if (ret2)
>          printk(KERN_ERR "ahb init failed: %d\n", ret2);
>
>      if (ret1 && ret2)
>          return ret1;
>
>      /* registered to at least one bus */
>      return 0;
> }

Thanks, this is better. however, if pci_register_driver() returns 0
while ath10k_ahb_init() returns error, it's better to unregister the
first bus, here is my another proposal:

        int ret;

        ret = pci_register_driver(&ath10k_pci_driver);
        if (ret) {
                printk(KERN_ERR "failed to register ath10k pci driver: 
%d\n",
                       ret);
                return ret;
        }

        ret = ath10k_ahb_init();
        if (ret) {
                printk(KERN_ERR "ahb init failed: %d\n", ret);
                pci_unregister_driver(&ath10k_pci_driver);
                return ret;
        }

        return 0;

If you agree, I will send v2 with this.

> .